Applies to: EUTs with analogue or digital inputs and analogue or digital outputs.
Aim: To measure the inter-channel cross-talk between the channels of the EUT at a range of
frequencies.
MethodThe input of the EUT's driven channel is fed with a sinusoidal stimulus at â€"20dBFS which is swept in
octave steps from 10Hz to the upper band-edge frequency. The input to the un-driven channel (if
digital) is fed with a digital-zero signal or (if analogue) is terminated with 50R (or 25R if unbalanced).
At each frequency, the ratio of the RMS amplitude of the output of the un-driven channel (measured
through a 1/3 octave band-pass filter at the stimulus frequency) to the RMS amplitude of the output of
the driven channel is measured, and displayed graphically in dB against frequency. The un-driven
and driven channels are reversed and the test is repeated. The two channels are overlaid on the
same axes so that worst-case cross-talk can be easily seen.
ConclusionThe UP exhibits a maximum cross-talk of 110dB all of the way up to 10kHz and at least 107dB at 20KHz. Below 1kHz the cross-talk is at least 125 dB !
Compared with DEQX from Stereophile (https://www.stereophile.com/content/allnic-d-5000-dht-da-processor-measurements-0) .
Quote"Channel separation was excellent, at >115dB in both directions below 1kHz, and still 95dB at 20kHz."
we can see that the Ultimate-Preamplifier is indeed superior in terms of channel separation and cross-talk !
Referenceshttp://resources.prismsound.com/tm/dS3_Applications_Manual_A4nc.pdf